In this last error, in the supposition that when I say You ought to do this I must mean You are commanded to do this, we have one of the reasons which has led to the supposition that the particular supersensible property by reference to which good must be defined is Will. And that ethical conclusion may be obtained by enquiring into the nature of a fundamentally real Will seems to be by far the commonest assumption of Metaphysical Ethics at the present day. But this assumption seems to owe its plausibility, not so much to the supposition that ought expresses a command, as to a far more fundamental error. This error consists in supposing that to ascribe certain predicates to a thing is the same thing as to say that that thing is the object of a certain kind of psychical state. It is supposed that to say that a thing is real or true is the same thing as to say that it is known in a certain way; and that the difference between the assertion that it is good and the assertion that it is real—between an ethical, therefore, and a metaphysical proposition—consists in the fact that whereas the latter asserts its relation to Cognition the former asserts its relation to Will. (§ 77 ¶ 1)

Now that this is an error has been already shewn in Chapter I. That the assertion This is good is not identical with the assertion This is willed, either by a supersensible will, or otherwise, nor with any other proposition, has been proved; nor can I add anything to that proof. But in face of this proof it may be anticipated that two lines of defence may be taken up. (1) It may be maintained that, nevertheless, they really are identical, and facts may be pointed out which seem to prove that identity. Or else (2) it may be said that an absolute identity is not maintained: that it is only meant to assert that there is some special connection between will and goodness, such as makes an enquiry into the real nature of the former an essential step in the proof of ethical conclusions. In order to meet these two possible objections, I propose first to shew what possible connections there are or may be between goodness and will; and that none of these can justify us in asserting that This is good is identical with This is willed. On the other hand it will appear that some of them may be easily confused with this assertion of identity; and that therefore the confusion is likely to have been made. This part of my argument will, therefore, already go some way towards meeting the second objection. But what must be conclusive against this is to shew that any possible connection between will and goodness except the absolute identity in question, would not be sufficient to give an enquiry into Will the smallest relevance to the proof of any ethical conclusion. (§ 77 ¶ 2)